Stepchild wants to see finances and money spent on his stepsiblings.

A son wanting to know what is going on about the capital he expects to inherit from his grandfather on his father's death is reasonable, if in exceedingly poor taste. Since he already does know about this, though, he has no need to enquire further; but he is clearly a bit neurotic and in need of reassurance that he is not being stolen from by his father. (This is obviously not an insult to his father at all, no, no, not even slightly.)

Wanting to know all the details of what is spent by his father on his stepmother and step-siblings, with the requirement that an accounting be kept and every penny spent on them be taken from his stepmother and given to him and his sibling when their father dies, is not reasonable and I do hope is not going to happen no matter how much he may threaten to cut his father off. (Which also isn't going to happen because, as pointed out, Bank of Daddy.).

No, it is not even vaguely reasonable.

The income from the "not quite a trust" is OP's husband's to spend how he wants. He could spend it all on alcohol and drink himself into an early grave if he wants and his children would have no say in that. He could give it all to charity and his children would have no say in that. The fact he chooses to spend some of it on OP and her children does not magically give them the right to dictate what he does.

The capital in the "not quite a trust" will go to OP's stepchildren when her husband dies, in line with FiL's wishes. That is the only money they have any right to.

I think it’s reasonable if by your kids you mean your children that aren’t with your current husband. Presumably your FiL didn’t work to set up a fund to spend money on children who weren’t related to him. If your husband wants to save the relationship with his son I suggest you butt out and he arranges a meeting with his children where he listens to them and their concerns.

The dad is not worried that he's going to cut his own child off FFS. The dad is worried because the child is going to cut himself off because he's not used to hearing the word no.

If the dad says, quite rightly, sorry you are not entitled to these demands, he's predicting the boy having a tantrum of great severity. That's what the dad thinks is going to "ruin the relationship." Then the boy will potentially lead his siblings down the same path, with the help of his ex wife who's already instigating similar behaviour. (See other thread re wedding.)

I don't think the dad needs to worry too much though, about "the relationship will never recover.". The boy is too money orientated and greedy to stray too far from the bank of dad for long. He'll be wanting his uni hand outs.

Then we've got OP who insists she has her own money and an ex who provides "over and above" for her children, yet between them couldn't afford one school trip for their child, and this "new dad" bankrolled that too.

I think OP and her step son have a lot more in common than she'd like to admit. Both buzzing around a honeypot they feel entitled too.

No, hes just a child and needs putting in his place. You dont write a child out of your will for being inappropriate. We would all be disinheriting several of our children of we did. But you make it absolutely clear how inappropriate it is.

Absolutely none of your step childs business. And he should be firmly told so. Its also not his business how your husband and you choose to spend your money. I would think this is a badly behaved teen who is legally an adult but is still very much a child. I have 6 kids. Eldest 39 youngest 19. My husband is stepdad to my elder 4, one of the other 2 is his and mine and I have a stepdaughter. He has his own business. Not a single one of our kids would dare to ask to see our finances. The younger 2 work for my husbands business but what happens in the future with our finances is absolutely our decision and not any of the kids. Someone hasnt set rules and boundaries with your stepson and he is stepping right over the line and needs closing down until hes actually grown up and understands this.

How on earth does an 18 year old get so entitled that he thinks his father needs to justify his own spending to his son?!

OP has DH spoken to his son properly and told him that it’s none of his business and how dare he be so outrageously rude??? why is he afraid to have that conversation?

What will happen if he calmly tells his son that his own finances are his own affair and he chooses not to share them? Parents often have to say “no” to children. The children are often annoyed, but it’s not the end of the world and things move on. Why will this cause such a backlash?

Has he never said “no” before? Is his son unusually angry and mean-spirited?

Hm what? Your husband’s money is now your money and it will go to you unless there’s a will in place specifying something else?

"The income from these assets is not your inheritance. It is my money to spend on whatever I like.

When I die, then you will be inheriting your share of the assets and associated income. Only then will it be your money to spend on whatever you like."

Not answering for the poster but my observation is that a lot of people post solely from their own experience and a lot of bitterness and lack of responsibility gets projected.

for example - your parents may have stayed together, or you stayed in a miserable marriage in the belief it was best for the child. You may firmly believe that every divorce is devastating for the child. But that belief doesnt make it true. There may be (there definitely are) many families that navigate divorce well. The problem comes from people who don’t seem to understand that there are other valid options.

I also find that there are people who don’t want to take responsibility for their own actions. It can be easier to blame your parents for messing up your life than accept that you are making choices all the time and you have options. Depending on the level of fucked up your parents were, the process of dealing with it may be longer, more complicated, and more painful. You may need help with it. And it may be an ongoing process. I am in no way downplaying that. But it’s too easy to keep blaming parents or others and some people love the victim role because it absolves them of all responsibility. Holding bitterness only damages the holder - it does not change the past or improve the future.

a lot of people on this post misread what OP said about her husbands fear about the impact on his relationship with his son. That’s projection. Lots have bashed OP. That’s also projection and a lot of bitterness. There are even people adamantly stating what the GF would have wanted. It’s not just simplistic, it’s being blind in some regards and says more about those posters than the actual situation.

Key point here is that it’s not the father’s income that is a direct inheritance for DSS. His inheritance is the trust assets that create that income.

the income doesn’t appear to be depleting the assets, it’s the interest so DSS would NEVER have access to this income, the income itself comes from the assets, is then divided up between those inheriting once his dad and the surviving siblings are dead.

there is nothing to reimburse per se. There are no arrangements or stipulations on what DH can do with any liquid savings he accumulates, he could spend the lot if he so wishes.

the vitriol aimed at @Greenhairedmonstor is astounding, but this is MN, all stepmothers are evil.

even when previous threads showing actions by this DSc mother show that SHES the one winding people up, she’s the one grabbing and causing rifts.

Fair point.

The Son is planning way ahead he wants all current spending analysed and recorded and repaid to his DFs estate at the time of his death. This could be 10 20 30 years away. How can this be about affording university ? it is pure greed. When someone receives an inheritance, be it the income or the capital it is theirs to do with as they wish .
In this case the DF can spend the income as he wishes and when the DS receives the final
distribution of the capital he can make his own choice.

He won't change if nobody ever challenges him on his behaviour, will he?

So I met someone that did change and you met someone who didn’t, or arguably so did if she was being friendly? So some people change. Just like this 18 year old may well grow up and change. And people do bad things for emotionally complicated reasons.

And yes I think MN ignores basic psychology - like maybe daddy moving another family in didn’t do wonders for his son’s emotional wellbeing, when it suits a certain agenda

I don’t think he should let this ruin his relationship with his children. They might be afraid that they won’t be able to afford university or to become independent. They might be afraid everything will be taken off them and given to you and your children? Maybe they were encouraged to ask by their mum/friends? All legitimate fears and finances shouldn’t be ‘secret’ really.

I think your dh should simply explain there’s money to support them but they don’t get to scrutinise his personal finances.

One of the girls who bullied me at school bounced over to me about ten years later, greeted me by name, and started burbling on about what fun we had together at school.

Sorry, I am not sure what your point was. That Mumsnet goes for simplistic answers? That Mumsnet posters will go along with the loudest voices when seeking explanations?

One of the girls who bullied me in school came over to me in a pub a few years later & apologised and has since taken her own life. Life & human emotion are complicated things.

Ach, it's Mumsnet; it is always a father's fault, and always a stepmother's fault, and when both are involved in the question around which a thread is being spun, it would not be possible for neither of them to be turned into baby-barbecuing bastards who torture fluffy kittens in their spare time while burning ten pound notes rather than letting the man's children have an ice-cream. In general they both will be.

Sigh.

The idea that someone other than a stepmother or a father might be culpable is very difficult to grasp, but those of us who live in the real world do know characters we'd cross the road to avoid, who are neither step-parents, nor fathers, nor the products of broken homes, but are just gits, often from an early age. (And they are not ND, before anyone thinks that might excuse them; just nasty.) I mean, goodness, some of us were even at school with such people.

He shouldn't be challenging any younger children on who paid for them to go somewhere. I would love to know why he asked about the funding for a trip that the OP's sister took her niece on. There is an answer but nobody likes it, apparently, because it makes us all meanies.

Can you conceive of the possibility that the elder of his sons by the ex might be the one influencing the younger sib with whom he lives? Even (gasp) following the ex's lead and influencing the younger boy against their father, his new wife and her children? Because that seems to me to be likely to be what the father is afraid of. I see no suggestion there that the father intends to punish the younger son in any way whatever.

But then, posters here have invented him having been reported by the OP as planning to punish the older son, so there is no limit to the ingenuity employed to bring blame to bear on him (for inhumanly planning to help his eldest son financially at university, the evil bastard that he clearly is: "He supports them and SS will be supported at university."), and on the OP for "stirring" – which I find particularly ironic given that her apparently automatic reaction to the trouble was to try to work out how she could make a (misplaced) effort to try to make things better between father and son by trying to pacify the son and obey his command to explain her private finances to him.

If the son will de-escalate, it seems very unlikely that the father, who did not start this incivility and prying and who has not done anything to perpetuate it as far as we know, would not be perfectly happy to accept an acknowledgement that someone else's financial affairs are none of his child's damn business except insofar as the involve an inheritance for the child from his grandfather – all about which we have been told the son already knows.

In the matter of bullying the (then eleven-year-old?) child: quizzing him about who paid for the school trip he was excited about having been on is the specific instance of bullying to which I was referring. Thoroughly nasty in the elder boy, that: who is he to spoil someone else's pleasure in a holiday by questioning the child's right to it?

You are right the OPs other stepchild she mentions isn’t 12 she says the younger one is 13 my mistake. Read the OPs comments again she states
‘This has been a bitter blow to my husband and he doesn’t see how his relationship with his child(ren) will recover.’ and
‘My husband is really upset and thinks this is the end of their relationship and it will affect his relationship with his younger child as well.’
So I’d still like to know why the younger DC is being brought into this.
It’s also interesting you say the 12 year old gets bullied - even the OP never says this. Then you quote some stuff that isn’t even in my post.
As my post does say, he’s totally in the wrong but he’s 18 and clearly jealous and not OK with this new family set up. It must be hard to hear all that gratitude for the skiing holiday etc when your family has been split up.
So I still advocate de-escalating instead of causing permanent family turmoil.

This.

Nowhere has the OP suggested that the father is contemplating punishing the new-adult son, or cutting him off, or any such thing; as for the suggestion he might punish the younger child for the offensiveness of his older brother, I would be interested to see the quote from the OP (as opposed to any of the other people posting here) that leads you to it. And the younger brother of the husband's ex is not twelve; that's the OP's child, the one the eighteen year old, then seventeen, bullied about the school skiing-trip. Nor has the OP suggested the twelve year old did anything other than go on a bit about something which had just happened and he'd greatly enjoyed.

I notice you don't mention that same seventeen-year-old demanding to know who paid for the OP's sister to take the OP's younger child out for the evening. Is there a "she was taunting him about his dad spending money on her" explanation for that?